Please note. There is no guarantee your display will support the resolution/framerate produced by this.
But if you are currently running a monitor at a non native resolution, then this may be worth a try.

Until I found this thread, I only managed to get it working at DMT mode 14 which isnt the native resolution (848*480) and made the image a bit blurry. The controller board takes a lot of different resolutions and scales them. There are no proper EDID entries so I had to use hdmi_ignore_edid=...

Now it seems to work just fine! At least it looks ok and "tvservice -m DMT" lists only one mode - 87. Your /boot/config.txt needs theese entries (no need of ignoring EDID with CVT):

I've been trying to get my RPi to work with a Matrox TripleHead2Go. This creates a virtual very-wide screen, which is split to multiple screens.

Many of the 3 display modes that it supports require a dual-link DVI connection, and frankly I would not expect the RPi to cope with a resolution of - say - 5760x1080. But there are very interesting lower resolution modes that would enable the RPi to use two displays, eg: 2x 1024x768, 2x 1280x800, 3x 800x600. Obviously these modes have quite extreme aspectratios (24:9, 32:10, 36:9 respectively, for the example above). Could this work with the new firmware?

I'm attaching an edid.dat from the TripleHead2Go. The box comes with software that lets the user select up to 4 modes to put in the edid. In this case I had selected 3x1280x800, 3x1024x768 (both of which I don't expect to work with the RPi), 2x1280x800 and 2x1024x768 (both of which I think could be made to work).

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1
# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
#disable_overscan=1
# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16
# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720
# uncomment if hdmi display is not detected and composite is being output
#hdmi_force_hotplug=1
# uncomment to force a specific HDMI mode (this will force VGA)
#hdmi_group=2
#hdmi_mode=16
# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
hdmi_drive=2
# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
config_hdmi_boost=4
# uncomment for composite PAL
#sdtv_mode=2
#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

How programmable are the timings for the sdtv (composite video) interface?. Is it possible to set non - standard line and frame rates, other than 625 line 50Hz and 525 line 60Hz?. It would be really useful to be able to use the Pi as a test card generator, maybe even stream video, for the old 405 line Tv standard (405 lines, 50Hz Interlaced) for us odd people who like to restore the odd vintage TV.

I am trying to run an LCD display at 480 x 272 connected through a TI DVI to 24-Bit RGB chip. Should the mode commands work down even at this very low resolution? I have been unable to get a viable image.

sgunther wrote:I am trying to run an LCD display at 480 x 272 connected through a TI DVI to 24-Bit RGB chip. Should the mode commands work down even at this very low resolution? I have been unable to get a viable image.

I have a square (yes, square! aspect ratio of one!) screen that has a screen resolution of 960 x 960, and i'm trying to use my raspberry pi to play videos on it in response to various sensor stimuli.

I managed to get the resolution of the desktop on boot to be correct by adding a custom HDMI mode:

<code>
hdmi_cvt=960 960 60
</code>

To test it, I cropped a video to 960 x 960 to play with omxplayer (which seems the right resolution when I play it on another computer); however, when I play it with omxplayer on my raspberry pi, it's highly distorted -- it looks like it's playing at something like 960 px tall x 320 px wide.

scottnla wrote:I have a square (yes, square! aspect ratio of one!) screen that has a screen resolution of 960 x 960, and i'm trying to use my raspberry pi to play videos on it in response to various sensor stimuli.

I managed to get the resolution of the desktop on boot to be correct by adding a custom HDMI mode:

<code>
hdmi_cvt=960 960 60
</code>

To test it, I cropped a video to 960 x 960 to play with omxplayer (which seems the right resolution when I play it on another computer); however, when I play it with omxplayer on my raspberry pi, it's highly distorted -- it looks like it's playing at something like 960 px tall x 320 px wide.

Any thoughts on why it is so highly distorted?

Might be the aspect ratio. Is it better with:
hdmi_cvt=960 960 60 1
and worse with
hdmi_cvt=960 960 60 3